Hi,

For my chevy Silverado K1500 5.7l TBI automatic gear 1995Please two bugs, but no error codes.

First one : first started in the journey, idle speed moves 5 seconds and a slight black smoke came out of the exhaust, then everything returned to normal. It didn't happen again all the day. This happen every day.

Second bug : During all the startup in the journey the idle speed moves between 900 and 1100 and only stabilizes when you engage a gear. So it is good as long as the gear is engaged and fluctuates sometime in neutral.

Thanks and Best journey.

JP

 

Hi,

May be a vaccum leak?

Thanks et Best journey.

 

Hi,

Help will be apreciate.

Code error for the first time since yesterday two times : number 32. I’ve already change the EGR valve and the sensor MAP.

Thanks.

 

My Haynes repair manual for the 1988-1998 year model GM trucks has the following diagnosis steps for the issue of erratic idle speed or loping during idle:

1. Vacuum leaks. Check mounting bolts at the intake manifold for tightness. Make sure all vacuum hoses are connected and in good condition. Use a stethoscope or a length of fuel hose held against your ear to listen for vacuum leaks while the engine is running. A hissing sound will be heard. A soapy water solution will also detect leaks. Check the intake manifold gasket surfaces.
2. Leaking EGR valve or plugged PCV valve.
3. Air filter clogged.
4. Fuel pump not delivering sufficient fuel.
5. Leaking head gasket. Perform a cylinder compression check.
6. Timing chain worn.
7. Camshaft lobes worn.
8. Valve clearance out of adjustment. Valves burned or otherwise leaking.
9. Ignition timing out of adjustment.
10. Ignition system not operating properly.
11. Thermostatic air cleaner not operating properly.
12. Dirty or clogged injectors.

 

Hi,
first sorry for my english.
Thank you very much for your answers.
I also have the Haynes manual and I noticed
all the causes that could make this type of breakdown.
I would like to find someone on the forum who could
guide me in more details regarding the symptoms.
I will try to eliminate point by point in order
to target the breakdow.
Thank again and have a great journey.